diff --git a/core/forms.py b/core/forms.py
index 11c4329..f1fb5ef 100644
--- a/core/forms.py
+++ b/core/forms.py
@@ -189,6 +189,13 @@ class CollectionForm(forms.ModelForm):
 
 
 class ApiKeyForm(forms.ModelForm):
+    def __init__(self, *args, user=None, **kwargs):
+        super().__init__(*args, **kwargs)
+        if user and user.is_authenticated:
+            self.fields['tags'].queryset = Tag.objects.filter(items__owner=user).distinct().order_by('name')
+        else:
+            self.fields['tags'].queryset = Tag.objects.none()
+
     class Meta:
         model = ApiKey
         fields = ['name', 'tags']
diff --git a/core/templates/core/collection_detail.html b/core/templates/core/collection_detail.html
index 3c11b71..6ca0498 100644
--- a/core/templates/core/collection_detail.html
+++ b/core/templates/core/collection_detail.html
@@ -13,7 +13,10 @@
           {% for tag in collection.filter_tags.all %}<span class="badge rounded-pill text-bg-light">#{{ tag.name }}</span>{% endfor %}
         </div>
       </div>
-      {% if can_edit %}<a class="btn btn-dark" href="{% if collection.mode == 'tags' %}{% url 'collection_edit' collection.id %}{% else %}{% url 'collection_manage' collection.id %}{% endif %}">{% trans "Edit collection" %}</a>{% endif %}
+      <div class="d-flex gap-2">
+        <a class="btn btn-outline-secondary" href="{% url 'collection_export' collection.id %}" hx-boost="false">{% trans "Export" %}</a>
+        {% if can_edit %}<a class="btn btn-dark" href="{% if collection.mode == 'tags' %}{% url 'collection_edit' collection.id %}{% else %}{% url 'collection_manage' collection.id %}{% endif %}">{% trans "Edit collection" %}</a>{% endif %}
+      </div>
     </div>
     {% if collection.description %}<div class="content lead mt-4">{{ collection.description|markdown }}</div>{% endif %}
   </header>
@@ -27,7 +30,7 @@
 
   <div class="collection-flow content">
     {% if collection.mode == 'tags' %}
-      {% for item in tag_items %}<section id="item-{{ item.id }}" class="collection-flow-section">{{ item|collection_item_markdown }}{% if item.comment %}<div class="text-muted border-start ps-3 mt-3">{{ item.comment|markdown }}</div>{% endif %}</section>{% empty %}<div class="text-center text-muted py-5">{% trans "No entries match the selected tags and types yet." %}</div>{% endfor %}
+      {% for item in tag_items %}<section id="item-{{ item.id }}" class="collection-flow-section{% if item.kind == 'todo' %} d-flex gap-3 align-items-start{% endif %}">{% if item.kind == 'todo' %}<form method="post" action="{% url 'toggle_done' item.id %}" hx-boost="false" class="pt-1">{% csrf_token %}<input type="hidden" name="next" value="{{ request.get_full_path }}#item-{{ item.id }}"><input class="form-check-input" type="checkbox" {% if item.is_done %}checked{% endif %} {% if item.can_toggle_done %}onchange="this.form.submit()"{% else %}disabled{% endif %} aria-label="{% trans 'Done' %}"></form><div class="flex-grow-1 {% if item.is_done %}text-decoration-line-through text-muted{% endif %}">{% endif %}{{ item|collection_item_markdown }}{% if item.comment %}<div class="text-muted border-start ps-3 mt-3">{{ item.comment|markdown }}</div>{% endif %}{% if item.kind == 'todo' %}</div>{% endif %}</section>{% empty %}<div class="text-center text-muted py-5">{% trans "No entries match the selected tags and types yet." %}</div>{% endfor %}
     {% else %}
       {% for section in sections %}{% include 'core/_collection_section_read.html' with section=section %}{% empty %}<div class="text-center text-muted py-5">{% trans "This collection has no sections yet." %}</div>{% endfor %}
     {% endif %}
diff --git a/core/templates/core/index.html b/core/templates/core/index.html
index 5b5a275..7363051 100644
--- a/core/templates/core/index.html
+++ b/core/templates/core/index.html
@@ -46,7 +46,7 @@
 <div class="row g-4">
   <aside class="col-lg-3 order-lg-2 mobile-filter-sidebar">
     <div class="filter-panel">
-      <div class="fw-semibold mb-2 filter-panel-title">{% trans "Filter" %}</div>
+      <div class="d-flex justify-content-between align-items-center mb-2 filter-panel-title"><div class="fw-semibold">{% trans "Filter" %}</div><a class="btn btn-sm btn-outline-secondary" href="{% url 'export_items' %}{% if request.GET.urlencode %}?{{ request.GET.urlencode }}{% endif %}" hx-boost="false">{% trans "Export" %}</a></div>
       <div class="d-flex flex-wrap gap-2 mb-3 filter-buttons">
         <a class="btn btn-sm {% if active_kind == 'todo' %}btn-primary{% else %}btn-outline-primary{% endif %}" href="{% if active_kind == 'todo' %}{% query_replace kind=None %}{% else %}{% query_replace kind='todo' %}{% endif %}">Todos{% if active_kind == 'todo' %} ×{% endif %}</a>
         <a class="btn btn-sm {% if active_kind == 'note' %}btn-secondary{% else %}btn-outline-secondary{% endif %}" href="{% if active_kind == 'note' %}{% query_replace kind=None %}{% else %}{% query_replace kind='note' %}{% endif %}">{% trans "Notes" %}{% if active_kind == 'note' %} ×{% endif %}</a>
diff --git a/core/tests.py b/core/tests.py
index 3b2a526..18634e4 100644
--- a/core/tests.py
+++ b/core/tests.py
@@ -241,13 +241,18 @@ class NavigationAndLayoutTests(TestCase):
         response = self.client.get(reverse('edit_item', args=[item.id]))
         self.assertContains(response, 'inline-edit-form')
 
-    def test_tag_filter_list_depends_on_current_filters_but_composer_gets_all_tags(self):
+    def test_tag_filter_list_depends_on_current_filters_but_composer_gets_visible_tags(self):
         open_todo = Item.objects.create(owner=self.user, kind=Item.Kind.TODO, content='Open #openonly')
         open_todo.sync_metadata()
         done_todo = Item.objects.create(owner=self.user, kind=Item.Kind.TODO, content='Done #archiveonly', is_done=True)
         done_todo.sync_metadata()
         note = Item.objects.create(owner=self.user, kind=Item.Kind.NOTE, content='Note #noteonly')
         note.sync_metadata()
+        other = get_user_model().objects.create_user(username='other-tags', password='secret')
+        foreign = Item.objects.create(owner=other, kind=Item.Kind.NOTE, content='Foreign #foreignonly')
+        foreign.sync_metadata()
+        public = Item.objects.create(owner=other, kind=Item.Kind.NOTE, content='Public #publiconly', visibility=Item.Visibility.PUBLIC)
+        public.sync_metadata()
 
         response = self.client.get(f'{reverse("index")}?status=archive')
         html = response.content.decode()
@@ -257,11 +262,30 @@ class NavigationAndLayoutTests(TestCase):
         self.assertNotIn('#noteonly', filter_tags)
         self.assertIn("'openonly'", html)
         self.assertIn("'noteonly'", html)
+        self.assertIn("'publiconly'", html)
+        self.assertNotIn('foreignonly', html)
 
         response = self.client.get(f'{reverse("tag_list")}?status=archive')
         self.assertContains(response, '#archiveonly')
         self.assertNotContains(response, '#openonly')
 
+    def test_tag_api_returns_only_visible_tags(self):
+        own = Item.objects.create(owner=self.user, content='Own #ownapi')
+        own.sync_metadata()
+        other = get_user_model().objects.create_user(username='other-api-tags', password='secret')
+        foreign = Item.objects.create(owner=other, content='Foreign #foreignapi')
+        foreign.sync_metadata()
+        public = Item.objects.create(owner=other, content='Public #publicapi', visibility=Item.Visibility.PUBLIC)
+        public.sync_metadata()
+
+        response = self.client.get(reverse('api_tags'))
+
+        self.assertEqual(response.status_code, 200)
+        tags = response.json()['tags']
+        self.assertIn('ownapi', tags)
+        self.assertIn('publicapi', tags)
+        self.assertNotIn('foreignapi', tags)
+
     def test_due_filter_also_shows_next_seven_days_separately(self):
         today = timezone.localdate()
         due = timezone.make_aware(datetime.combine(today, time(12, 0)))
@@ -589,6 +613,36 @@ class CollectionTests(TestCase):
         manage_response = self.client.get(reverse('collection_manage', args=[collection.id]))
         self.assertRedirects(manage_response, reverse('collection_edit', args=[collection.id]))
 
+    def test_tag_collection_todos_are_rendered_with_checkbox(self):
+        todo = Item.objects.create(owner=self.user, kind=Item.Kind.TODO, content='Check me #project')
+        todo.sync_metadata()
+        collection = Collection.objects.create(
+            owner=self.user, title='Typed tags', mode=Collection.Mode.TAGS,
+            include_notes=False, include_todos=True,
+        )
+        collection.filter_tags.add(Tag.objects.get(name='project'))
+
+        response = self.client.get(collection.get_absolute_url())
+
+        self.assertContains(response, 'type="checkbox"')
+        self.assertContains(response, reverse('toggle_done', args=[todo.id]))
+
+    def test_tag_collection_todo_checkbox_toggles_and_returns_to_collection(self):
+        todo = Item.objects.create(owner=self.user, kind=Item.Kind.TODO, content='Check me #project')
+        todo.sync_metadata()
+        collection = Collection.objects.create(
+            owner=self.user, title='Typed tags', mode=Collection.Mode.TAGS,
+            include_notes=False, include_todos=True,
+        )
+        collection.filter_tags.add(Tag.objects.get(name='project'))
+        next_url = f'{collection.get_absolute_url()}#item-{todo.id}'
+
+        response = self.client.post(reverse('toggle_done', args=[todo.id]), {'next': next_url})
+
+        self.assertRedirects(response, next_url, fetch_redirect_response=False)
+        todo.refresh_from_db()
+        self.assertTrue(todo.is_done)
+
     def test_tag_collection_can_filter_included_item_types(self):
         note = Item.objects.create(owner=self.user, kind=Item.Kind.NOTE, content='Matching note #project')
         note.sync_metadata()
@@ -617,6 +671,35 @@ class CollectionTests(TestCase):
         self.assertContains(response, 'name="include_links"')
         self.assertContains(response, 'name="include_journal"')
 
+    def test_current_list_can_be_exported_as_markdown(self):
+        Item.objects.create(owner=self.user, kind=Item.Kind.TODO, content='Open task #project').sync_metadata()
+        Item.objects.create(owner=self.user, kind=Item.Kind.NOTE, content='Other note')
+
+        response = self.client.get(f'{reverse("export_items")}?kind=todo&tag=project')
+
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(response['Content-Type'], 'text/markdown; charset=utf-8')
+        body = response.content.decode()
+        self.assertIn('- [ ] Open task #project', body)
+        self.assertNotIn('Other note', body)
+
+    def test_collection_can_be_exported_as_markdown(self):
+        collection = Collection.objects.create(owner=self.user, title='Reading view', description='Guide')
+        todo = Item.objects.create(owner=self.user, kind=Item.Kind.TODO, content='Todo section #project')
+        note = Item.objects.create(owner=self.user, kind=Item.Kind.NOTE, content='## Note section #project')
+        CollectionSection.objects.create(collection=collection, item=todo, position=0)
+        CollectionSection.objects.create(collection=collection, item=note, position=1)
+
+        response = self.client.get(reverse('collection_export', args=[collection.id]))
+
+        self.assertEqual(response.status_code, 200)
+        body = response.content.decode()
+        self.assertIn('# Reading view', body)
+        self.assertIn('Guide', body)
+        self.assertIn('- [ ] Todo section', body)
+        self.assertIn('## Note section', body)
+        self.assertNotIn('#project', body)
+
     def test_collection_opens_as_continuous_reading_view(self):
         collection = Collection.objects.create(owner=self.user, title='Reading view')
         first = Item.objects.create(owner=self.user, kind=Item.Kind.NOTE, content='First paragraph')
@@ -761,6 +844,31 @@ class ApiItemFilterTests(TestCase):
         item.sync_metadata()
         return item
 
+    def test_api_key_settings_only_offer_own_tags(self):
+        self.client.force_login(self.user)
+        self.create_item('Own tag #own')
+        other = get_user_model().objects.create_user(username='api-other', password='secret')
+        other_item = Item.objects.create(owner=other, content='Other tag #foreign')
+        other_item.sync_metadata()
+
+        response = self.client.get(reverse('settings'))
+        api_section = response.content.decode().split('id="api"', 1)[1]
+
+        self.assertIn('#own', api_section)
+        self.assertNotIn('#foreign', api_section)
+
+    def test_api_key_cannot_be_created_with_foreign_tag(self):
+        self.client.force_login(self.user)
+        other = get_user_model().objects.create_user(username='api-other', password='secret')
+        other_item = Item.objects.create(owner=other, content='Other tag #foreign')
+        other_item.sync_metadata()
+        foreign_tag = Tag.objects.get(name='foreign')
+
+        response = self.client.post(reverse('settings'), {'action': 'apikey', 'name': 'Bad key', 'tags': [foreign_tag.id]})
+
+        self.assertEqual(response.status_code, 200)
+        self.assertFalse(ApiKey.objects.filter(owner=self.user, name='Bad key').exists())
+
     def test_api_key_scope_and_request_tags_are_combined(self):
         matching = self.create_item('Keyboard shortcuts #help #tasten')
         self.create_item('Git help #help #git')
@@ -775,6 +883,19 @@ class ApiItemFilterTests(TestCase):
         ids = [item['id'] for item in response.json()['items']]
         self.assertEqual(ids, [matching.id])
 
+    def test_api_key_only_returns_owner_items_not_other_public_items(self):
+        own = self.create_item('Own public help #help')
+        other = get_user_model().objects.create_user(username='api-public-other', password='secret')
+        public = Item.objects.create(owner=other, content='Other public help #help', visibility=Item.Visibility.PUBLIC)
+        public.sync_metadata()
+
+        response = self.client.get(reverse('api_items'), HTTP_X_API_KEY=self.api_key.token)
+
+        self.assertEqual(response.status_code, 200)
+        ids = [item['id'] for item in response.json()['items']]
+        self.assertIn(own.id, ids)
+        self.assertNotIn(public.id, ids)
+
     def test_api_items_supports_limit_and_search(self):
         self.create_item('First #help #shell')
         second = self.create_item('Second #help #shell keyboard')
diff --git a/core/urls.py b/core/urls.py
index d16317f..2e6709f 100644
--- a/core/urls.py
+++ b/core/urls.py
@@ -8,6 +8,7 @@ urlpatterns = [
     path('logout/', auth_views.LogoutView.as_view(), name='logout'),
     path('invite/<str:token>/', views.accept_user_invite, name='accept_user_invite'),
     path('new/', views.new_item, name='new_item'),
+    path('export/', views.export_items, name='export_items'),
     path('journal/', views.journal, name='journal'),
     path('kanban/', views.kanban_list, name='kanban_list'),
     path('kanban/<int:pk>/', views.kanban_detail, name='kanban_detail'),
@@ -25,6 +26,7 @@ urlpatterns = [
     path('collections/<int:pk>/', views.collection_detail, name='collection_detail'),
     path('collections/<int:pk>/manage/', views.collection_manage, name='collection_manage'),
     path('collections/<int:pk>/edit/', views.collection_edit, name='collection_edit'),
+    path('collections/<int:pk>/export/', views.collection_export, name='collection_export'),
     path('collections/<int:pk>/delete/', views.collection_delete, name='collection_delete'),
     path('items/<int:pk>/', views.item_detail, name='item_detail'),
     path('items/<int:pk>/card/', views.item_card, name='item_card'),
diff --git a/core/views.py b/core/views.py
index 571b034..0794591 100644
--- a/core/views.py
+++ b/core/views.py
@@ -13,6 +13,7 @@ from django.db import transaction
 from django.db.models import Case, Count, IntegerField, ProtectedError, Q, Value, When
 from django.http import HttpResponse, JsonResponse
 from django.urls import reverse
+from django.utils.http import url_has_allowed_host_and_scheme
 from django.utils import timezone
 from django.utils import translation
 from django.utils.translation import gettext as _
@@ -21,6 +22,7 @@ from django.views.decorators.csrf import csrf_exempt
 from django.views.decorators.http import require_http_methods, require_POST
 from .forms import ApiKeyForm, CollectionForm, EditItemForm, InviteRegistrationForm, KanbanForm, QuickItemForm, TeamForm, TeamInviteForm, UserInviteForm, UserPreferenceForm, UserSettingsForm
 from .models import ApiKey, Attachment, Collection, CollectionSection, Item, Kanban, Tag, Team, TeamInvite, TeamMembership, UserInvite, UserPreference, TAG_RE, without_markdown_code
+from .templatetags.markdown_extras import strip_tags_outside_code
 
 TYPE_COMMAND_RE = re.compile(r'^/(todo|note|link|journal)\b', re.I)
 VISIBILITY_COMMAND_RE = re.compile(r'/(public|private)\b', re.I)
@@ -209,6 +211,13 @@ def user_can_edit_item(user, item):
     return item.owner_id == user.id or (item.team_id and TeamMembership.objects.filter(team=item.team, user=user).exists())
 
 
+def visible_tags(user):
+    """Tags from items the user may see; avoids leaking private tags from other users."""
+    if not user.is_authenticated:
+        return Tag.objects.filter(items__visibility=Item.Visibility.PUBLIC).distinct().order_by('name')
+    return Tag.objects.filter(items__in=visible_items(user)).distinct().order_by('name')
+
+
 def user_can_delete_item(user, item):
     return item.owner_id == user.id or (item.team_id and TeamMembership.objects.filter(team=item.team, user=user, role__in=[TeamMembership.Role.OWNER, TeamMembership.Role.ADMIN]).exists())
 
@@ -316,6 +325,137 @@ def index_filter_tags(request, user, prefs, active_tags=None):
     return Tag.objects.filter(Q(items__in=items) | Q(name__in=active_tags)).distinct().order_by('name')
 
 
+def index_filtered_items(request, prefs):
+    active_tags = [t.strip().lower() for t in request.GET.getlist('tag') if t.strip()]
+    active_tag_mode = 'all' if request.GET.get('tag_mode') == 'all' else 'any'
+    tag = active_tags[0] if active_tags else None
+    kind = request.GET.get('kind')
+    status = request.GET.get('status')
+    day = request.GET.get('day')
+    q = request.GET.get('q', '').strip()
+    items = visible_items(request.user)
+    applied_preferences = False
+    if active_tags:
+        if active_tag_mode == 'all':
+            for tag_name in active_tags:
+                items = items.filter(tags__name=tag_name)
+        else:
+            items = items.filter(tags__name__in=active_tags).distinct()
+    if kind in dict(Item.Kind.choices):
+        items = items.filter(kind=kind)
+    elif not any([tag, status, q, day]):
+        applied_preferences = True
+        type_filter = Q()
+        if prefs.show_notes:
+            type_filter |= Q(kind=Item.Kind.NOTE)
+        if prefs.show_links:
+            type_filter |= Q(kind=Item.Kind.LINK)
+        if prefs.show_journal:
+            type_filter |= Q(kind=Item.Kind.JOURNAL)
+        if prefs.show_open_todos:
+            type_filter |= Q(kind=Item.Kind.TODO, is_done=False)
+        if prefs.show_done_todos:
+            type_filter |= Q(kind=Item.Kind.TODO, is_done=True)
+        items = items.filter(type_filter) if type_filter else items.none()
+    if day:
+        items = items.filter(created_at__date=day)
+    upcoming_end = timezone.make_aware(datetime.combine(timezone.localdate() + timedelta(days=7), time(23, 59, 59)))
+    if status == 'open':
+        items = items.filter(kind=Item.Kind.TODO, is_done=False)
+    elif status == 'due':
+        items = items.filter(kind=Item.Kind.TODO, is_done=False, due_at__isnull=False, due_at__lte=upcoming_end).order_by('due_at', '-created_at')
+    elif status == 'archive':
+        items = items.filter(kind=Item.Kind.TODO, is_done=True)
+    elif not applied_preferences:
+        items = items.exclude(kind=Item.Kind.TODO, is_done=True)
+    if q:
+        items = items.filter(Q(content__icontains=q) | Q(url__icontains=q) | Q(tags__name__icontains=q)).distinct()
+    return items, active_tags, active_tag_mode, tag, kind, status, day, q
+
+
+def export_item_line(item, hide_tags=False):
+    content = strip_tags_outside_code(item.content) if hide_tags else (item.content or '')
+    lines = [line.rstrip() for line in content.strip().splitlines()]
+    first = lines[0] if lines else _('Untitled')
+    prefix = '- [x] ' if item.kind == Item.Kind.TODO and item.is_done else '- [ ] ' if item.kind == Item.Kind.TODO else '- '
+    output = [f'{prefix}{first}']
+    output.extend(f'  {line}' if line else '' for line in lines[1:])
+    if item.comment:
+        output.append('')
+        output.extend(f'  > {line}' if line else '  >' for line in item.comment.strip().splitlines())
+    return '\n'.join(output)
+
+
+def markdown_response(filename, markdown_text):
+    response = HttpResponse(markdown_text, content_type='text/markdown; charset=utf-8')
+    response['Content-Disposition'] = f'attachment; filename="{filename}"'
+    return response
+
+
+@login_required
+def export_items(request):
+    prefs, created = UserPreference.objects.get_or_create(user=request.user)
+    items, active_tags, active_tag_mode, tag, kind, status, day, q = index_filtered_items(request, prefs)
+    title_parts = [_('my2dos export')]
+    if kind:
+        title_parts.append(kind)
+    if active_tags:
+        title_parts.append(' '.join(f'#{tag_name}' for tag_name in active_tags))
+    if status:
+        title_parts.append(status)
+    if q:
+        title_parts.append(f'“{q}”')
+    lines = [f'# {" – ".join(title_parts)}', '']
+    lines.extend(export_item_line(item) for item in items)
+    return markdown_response('my2dos-export.md', '\n\n'.join(lines).strip() + '\n')
+
+
+def collection_item_export(item, level=2):
+    content = strip_tags_outside_code(item.content)
+    if item.kind == Item.Kind.TODO:
+        return export_item_line(item, hide_tags=True)
+    if re.match(r'^#{1,6}\s+', content.lstrip()):
+        body = content
+    else:
+        body = f'{"#" * level} {content}'
+    if item.comment:
+        body = f'{body}\n\n> ' + item.comment.strip().replace('\n', '\n> ')
+    return body
+
+
+def collection_sections_export(sections, level=2):
+    lines = []
+    for section in sections:
+        if section.item:
+            heading = section.title.strip() if section.title else ''
+            if heading:
+                lines.append(f'{"#" * level} {heading}')
+                lines.append(collection_item_export(section.item, level + 1))
+            else:
+                lines.append(collection_item_export(section.item, level))
+        elif section.sub_collection:
+            title = section.title or section.sub_collection.title
+            lines.append(f'{"#" * level} {title}')
+            if section.sub_collection.description:
+                lines.append(section.sub_collection.description.strip())
+            lines.append(collection_sections_export(section.sub_collection.sections.select_related('item', 'sub_collection').prefetch_related('item__tags', 'item__attachments'), level + 1))
+    return '\n\n'.join(line for line in lines if line).strip()
+
+
+def collection_export(request, pk):
+    collection = get_object_or_404(visible_collections(request.user), pk=pk)
+    lines = [f'# {collection.title}', '']
+    if collection.description:
+        lines.extend([collection.description.strip(), ''])
+    if collection.mode == Collection.Mode.TAGS:
+        lines.extend(export_item_line(item, hide_tags=True) for item in collection_tag_items(collection))
+    else:
+        body = collection_sections_export(collection.sections.select_related('item', 'sub_collection').prefetch_related('item__tags', 'item__attachments', 'sub_collection__sections__item', 'sub_collection__sections__sub_collection'))
+        if body:
+            lines.append(body)
+    return markdown_response(f'collection-{collection.pk}.md', '\n\n'.join(line for line in lines if line).strip() + '\n')
+
+
 def index(request):
     if not request.user.is_authenticated:
         if request.method == 'POST':
@@ -400,7 +540,7 @@ def index(request):
             default=Value(1), output_field=IntegerField(),
         )).order_by('due_rank', 'due_at', '-created_at')
     return render(request, 'core/index.html', {
-        'form': QuickItemForm(), 'items': items, 'tags': index_filter_tags(request, request.user, prefs, active_tags), 'composer_tags': Tag.objects.all(), 'item_kind_choices': Item.Kind.choices, 'selected_item_kind': prefs.default_item_kind, 'due_now_items': due_now_items, 'upcoming_due_items': upcoming_due_items, 'active_tag': tag, 'active_tags': active_tags, 'active_tag_mode': active_tag_mode, 'active_kind': kind, 'active_status': status, 'active_day': day, 'q': q, 'due_count': due_count, 'overview_lines': prefs.overview_lines,
+        'form': QuickItemForm(), 'items': items, 'tags': index_filter_tags(request, request.user, prefs, active_tags), 'composer_tags': visible_tags(request.user), 'item_kind_choices': Item.Kind.choices, 'selected_item_kind': prefs.default_item_kind, 'due_now_items': due_now_items, 'upcoming_due_items': upcoming_due_items, 'active_tag': tag, 'active_tags': active_tags, 'active_tag_mode': active_tag_mode, 'active_kind': kind, 'active_status': status, 'active_day': day, 'q': q, 'due_count': due_count, 'overview_lines': prefs.overview_lines,
     })
 
 
@@ -435,7 +575,7 @@ def new_item(request):
                 add_collection_section(collection, item)
             return redirect(next_url)
     return render(request, 'core/new_item.html', {
-        'form': QuickItemForm(), 'tags': Tag.objects.all(), 'requested_kind': requested_kind, 'next_url': next_url, 'collection': collection,
+        'form': QuickItemForm(), 'tags': visible_tags(request.user), 'requested_kind': requested_kind, 'next_url': next_url, 'collection': collection,
     })
 
 
@@ -474,7 +614,7 @@ def journal(request):
     next_month, next_year = (1, year + 1) if month == 12 else (month + 1, year)
     prefs, created = UserPreference.objects.get_or_create(user=request.user)
     return render(request, 'core/journal.html', {
-        'form': QuickItemForm(), 'items': items, 'tags': Tag.objects.all(), 'weeks': weeks, 'year': year, 'month': month, 'selected_day': selected_day,
+        'form': QuickItemForm(), 'items': items, 'tags': visible_tags(request.user), 'weeks': weeks, 'year': year, 'month': month, 'selected_day': selected_day,
         'prev_year': prev_year, 'prev_month': prev_month, 'next_year': next_year, 'next_month': next_month, 'overview_lines': prefs.overview_lines,
     })
 
@@ -515,7 +655,7 @@ def settings_view(request):
                 messages.success(request, _('Default view saved.'))
                 return redirect('settings')
         elif request.POST.get('action') == 'apikey':
-            key_form = ApiKeyForm(request.POST)
+            key_form = ApiKeyForm(request.POST, user=request.user)
             if key_form.is_valid():
                 api_key = key_form.save(commit=False)
                 api_key.owner = request.user
@@ -535,7 +675,7 @@ def settings_view(request):
     return render(request, 'core/settings.html', {
         'profile_form': UserSettingsForm(instance=request.user),
         'preference_form': UserPreferenceForm(instance=prefs),
-        'key_form': ApiKeyForm(),
+        'key_form': ApiKeyForm(user=request.user),
         'user_invite_form': UserInviteForm(),
         'user_invites': request.user.sent_user_invites.filter(accepted_at__isnull=True),
         'api_keys': request.user.api_keys.prefetch_related('tags'),
@@ -914,10 +1054,13 @@ def collection_edit(request, pk):
 
 def collection_detail(request, pk):
     collection = get_object_or_404(visible_collections(request.user), pk=pk)
+    tag_items = list(collection_tag_items(collection)) if collection.mode == Collection.Mode.TAGS else []
+    for item in tag_items:
+        item.can_toggle_done = item.kind == Item.Kind.TODO and user_can_edit_item(request.user, item)
     return render(request, 'core/collection_detail.html', {
         'collection': collection,
         'sections': collection.sections.select_related('item', 'sub_collection').prefetch_related('item__tags', 'item__attachments', 'sub_collection__sections__item', 'sub_collection__sections__sub_collection') if collection.is_structured else [],
-        'tag_items': collection_tag_items(collection) if collection.mode == Collection.Mode.TAGS else [],
+        'tag_items': tag_items,
         'can_edit': user_can_edit_collection(request.user, collection),
     })
 
@@ -1034,6 +1177,9 @@ def toggle_done(request, pk):
     item.is_done = not item.is_done
     item.completed_at = timezone.now() if item.is_done else None
     item.save(update_fields=['is_done', 'completed_at', 'updated_at'])
+    next_url = request.POST.get('next') or request.GET.get('next')
+    if next_url and url_has_allowed_host_and_scheme(next_url, allowed_hosts={request.get_host()}):
+        return redirect(next_url)
     if request.headers.get('HX-Request') and item.is_done and request.GET.get('status') != 'archive':
         return HttpResponse('')
     return render(request, 'core/_item.html', {'item': item})
@@ -1060,7 +1206,7 @@ def edit_item(request, pk):
             target_visibility, target_team = desired_item_scope(item, request.user, force_private=item.visibility == Item.Visibility.PRIVATE)
             if not item_scope_fits_collections(item, target_visibility, target_team):
                 form.add_error('visibility', _('This visibility is incompatible with a collection that uses the note.'))
-                return render(request, 'core/_edit_form.html', {'item': item, 'form': form, 'tags': Tag.objects.all()}, status=409)
+                return render(request, 'core/_edit_form.html', {'item': item, 'form': form, 'tags': visible_tags(request.user)}, status=409)
             item.visibility, item.team = target_visibility, target_team
             item.save()
             form.save_m2m()
@@ -1071,7 +1217,7 @@ def edit_item(request, pk):
             response = render(request, 'core/_item.html', {'item': item, 'overview_lines': request.user.preferences.overview_lines if hasattr(request.user, 'preferences') else 4})
             response['HX-Trigger'] = 'tagsChanged'
             return response
-    return render(request, 'core/_edit_form.html', {'item': item, 'tags': Tag.objects.all()})
+    return render(request, 'core/_edit_form.html', {'item': item, 'tags': visible_tags(request.user)})
 
 
 @login_required
@@ -1090,7 +1236,7 @@ def item_editor(request, pk):
             target_visibility, target_team = desired_item_scope(item, request.user, force_private=item.visibility == Item.Visibility.PRIVATE)
             if not item_scope_fits_collections(item, target_visibility, target_team):
                 form.add_error('visibility', _('This visibility is incompatible with a collection that uses the note.'))
-                return render(request, 'core/item_editor.html', {'item': item, 'form': form, 'tags': Tag.objects.all(), 'next_url': next_url}, status=409)
+                return render(request, 'core/item_editor.html', {'item': item, 'form': form, 'tags': visible_tags(request.user), 'next_url': next_url}, status=409)
             item.visibility, item.team = target_visibility, target_team
             item.save()
             form.save_m2m()
@@ -1099,7 +1245,7 @@ def item_editor(request, pk):
             item.sync_metadata()
             apply_team_from_tags(item, request.user, force_private=item.visibility == Item.Visibility.PRIVATE)
             return redirect(next_url)
-    return render(request, 'core/item_editor.html', {'item': item, 'tags': Tag.objects.all(), 'next_url': next_url})
+    return render(request, 'core/item_editor.html', {'item': item, 'tags': visible_tags(request.user), 'next_url': next_url})
 
 
 @login_required
@@ -1188,7 +1334,7 @@ def set_default_item_kind(request):
 
 @login_required
 def api_tags(request):
-    return JsonResponse({'tags': list(Tag.objects.order_by('name').values_list('name', flat=True))})
+    return JsonResponse({'tags': list(visible_tags(request.user).values_list('name', flat=True))})
 
 
 @login_required